The influence of water on visible-light initiated free-radical/cationic ring-opening hybrid polymerization of methacrylate/epoxy: polymerization kinetics, crosslinking structure and dynamic mechanical properties

Ge, Xueping; Ye, Qiang; Song, Linyong; Misra, Anil; Spencer, Paulette

doi:10.1039/c5ra14358f

Cited by 7 publications

(9 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Upon illumination in the UV range, creation of cations and radicals initiates both relevant reactions. [31] Contrary to diaryliodonium salts, which are often employed in initiator systems for radical and cationic hybrid polymerizations, [32][33][34] CAT2 cannot be activated by free radicals, due to its high reduction potential. [31] This eliminates unwanted epoxide curing during illumination at 455 nm.…”

Section: Resultsmentioning

confidence: 99%

High Resolution Dual Material Stereolithography for Monolithic Microdevices

Schmidleithner

Zhang

Taebnia

et al. 2021

Adv Materials Technologies

View full text Add to dashboard Cite

Functional 3D components such as perfusion channels and mechanical actuation elements at cellular length scales can support cell survival and tissue maturation in tissue modeling devices. These advanced requirements call for increasingly complex materials and 3D fabrication methods. Here, a high‐resolution dual‐material 3D printing concept is developed, where distinct materials are produced locally by orthogonal chemical reactions depending on the illumination wavelength. A tough, stiff epoxy network results from cationic polymerization in UV light, while a soft and diffusion‐open hydrogel forms by free‐radical polymerization initiated by blue light. Thus, dual‐exposure allows for selection of material properties in every voxel, while retaining the 3D design flexibility associated with stereolithography. This enables single‐process fabrication of devices integrating mechanically stable chip‐to‐world interconnects and compliant, diffusion‐open perfusable channel components of 150 µm in width and height, while also allowing structural and mechanical feature dimensions down to 60 µm. A perfusion chip capable of creating a stable uniaxial chemical gradient by passive dye diffusion through hydrogel sections, and a negative Poisson ratio structure based on the interplay between stiff rotators and compliant hinges, are manufactured as proof‐of‐concept microdevices. Lastly, week‐long culture of hydrogel‐encapsulated human liver cells demonstrates the cytocompatibility of both materials.

show abstract

Section: Resultsmentioning

confidence: 99%

High Resolution Dual Material Stereolithography for Monolithic Microdevices

Schmidleithner

Zhang

Taebnia

et al. 2021

Adv Materials Technologies

View full text Add to dashboard Cite

show abstract

“…One drop (5 µL) of the polymer-only control was placed on the crystal top plate of the ATR accessory and covered with a mylar film. After 30 spectra were collected, the resin was light irradiated for 40 s using a commercial light source (Spectrum ® 800) with an intensity of 550 mW/cm 2 [ 10 ]. The double bond conversion was monitored by the band ratio profile-1637cm −1 (C=C)/1710 cm −1 (C=O).…”

Section: Methodsmentioning

confidence: 99%

“…The prepared resins were injected into a Tzero ® Hermetic Lid (P/N: 900797.901) or Tzero ® low mass pan (P/N: 901683.901), covered with a dodecyltrichlorosilane-modified glass cover (22 mm × 30 mm, Fisherfinest ® ), then light-cured for 40 s at 23 ± 2 °C using a commercial visible light lamp (Spectrum ® 800, Dentsply, Milford, DE, USA. Intensity is 550 mW/cm 2 ) [ 10 ]. The polymerized samples were stored in the dark at 23 ± 2 °C for at least 48 h before testing.…”

Section: Methodsmentioning

confidence: 99%

“…Several natural, plant-derived compounds which offer antimicrobial properties, as well as mineral deposition, have been investigated [ 9 ]. Some of these strategies have offered multi-faceted advantages such as improved adhesion, enhanced mechanical properties [ 10 , 11 ], and antimicrobial properties [ 12 ]. However, the vulnerability of the adhesive system remains a challenge as none of these approaches address the complex interplay of the physicochemical and mechanical factors that challenge the durability of the adhesive seal at the composite-tooth interface.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Reconfigurable Dual Peptide Tethered Polymer System Offers a Synergistic Solution for Next Generation Dental Adhesives

Yuca

Xie

Song

et al. 2021

IJMS

Self Cite

View full text Add to dashboard Cite

Resin-based composite materials have been widely used in restorative dental materials due to their aesthetic, mechanical, and physical properties. However, they still encounter clinical shortcomings mainly due to recurrent decay that develops at the composite-tooth interface. The low-viscosity adhesive that bonds the composite to the tooth is intended to seal this interface, but the adhesive seal is inherently defective and readily damaged by acids, enzymes, and oral fluids. Bacteria infiltrate the resulting gaps at the composite-tooth interface and bacterial by-products demineralize the tooth and erode the adhesive. These activities lead to wider and deeper gaps that provide an ideal environment for bacteria to proliferate. This complex degradation process mediated by several biological and environmental factors damages the tooth, destroys the adhesive seal, and ultimately, leads to failure of the composite restoration. This paper describes a co-tethered dual peptide-polymer system to address composite-tooth interface vulnerability. The adhesive system incorporates an antimicrobial peptide to inhibit bacterial attack and a hydroxyapatite-binding peptide to promote remineralization of damaged tooth structure. A designer spacer sequence was incorporated into each peptide sequence to not only provide a conjugation site for methacrylate (MA) monomer but also to retain active peptide conformations and enhance the display of the peptides in the material. The resulting MA-antimicrobial peptides and MA-remineralization peptides were copolymerized into dental adhesives formulations. The results on the adhesive system composed of co-tethered peptides demonstrated both strong metabolic inhibition of S. mutans and localized calcium phosphate remineralization. Overall, the result offers a reconfigurable and tunable peptide-polymer hybrid system as next-generation adhesives to address composite-tooth interface vulnerability.

show abstract

“…The temperature was ramped at the rate of 3 • C/min from 20 to 180 • C. The testing parameters of the second scan were the same as the first scan. Glass transition temperature (T g ) is determined as the position of the maximum peak on tan δ versus temperature measured by DMA [33]. In addition, to determine the rubbery modulus and T g of soaked sample in dry conditions, the beam specimens were soaked in water at 37 • C for 1, 3, and 5-days, respectively.…”

Section: Dma Test and Prony Series Evaluationmentioning

confidence: 99%

Evolution of Network Structure and Mechanical Properties in Autonomous-Strengthening Dental Adhesive

Sarikaya

Song

et al. 2020

Polymers

Self Cite

View full text Add to dashboard Cite

The inherent degradation property of most dental resins in the mouth leads to the long-term release of degradation by-products at the adhesive/tooth interface. The by-products increase the virulence of cariogenic bacteria, provoking a degradative positive-feedback loop that leads to physicochemical and mechanical failure. Photoinduced free-radical polymerization and sol‒gel reactions have been coupled to produce a novel autonomous-strengthening adhesive with enhanced hydrolytic stability. This paper investigates the effect of network structure on time-dependent mechanical properties in adhesives with and without autonomous strengthening. Stress relaxation was conducted under 0.2% strain for 8 h followed by 40 h recovery in water. The stress‒time relationship is analyzed by nonlinear least-squares data-fitting. The fitted Prony series predicts the sample’s history under monotonic loading. Results showed that the control failed after the first loading‒unloading‒recovery cycle with permanent deformation. While for the experimental sample, the displacement was almost completely recovered and the Young’s modulus increased significantly after the first test cycle. The experimental polymer exhibited higher degree of conversion, lower leachate, and time-dependent stiffening characteristics. The autonomous-strengthening reaction persists in the aqueous environment leading to a network with enhanced resistance to deformation. The results illustrate a rational approach for tuning the viscoelasticity of durable dental adhesives.

show abstract

The influence of water on visible-light initiated free-radical/cationic ring-opening hybrid polymerization of methacrylate/epoxy: polymerization kinetics, crosslinking structure and dynamic mechanical properties

Cited by 7 publications

References 48 publications

High Resolution Dual Material Stereolithography for Monolithic Microdevices

High Resolution Dual Material Stereolithography for Monolithic Microdevices

Reconfigurable Dual Peptide Tethered Polymer System Offers a Synergistic Solution for Next Generation Dental Adhesives

Evolution of Network Structure and Mechanical Properties in Autonomous-Strengthening Dental Adhesive

Contact Info

Product

Resources

About